Risk factors for transmission of carbapenem-resistant Enterobacterales to healthcare personnel gloves and gowns in the USA

BACKGROUND

Hospitals are sources for acquisition of carbapenem-resistant Entero-bacterales (CRE), and it is believed that the contamination of healthcare personnel (HCP) hands and clothing play a major role in patient-to-patient transmission of antibiotic-resistant bacteria.

AIM

The aim of this study was to determine which HCP types, HCP-patient interactions, and patient characteristics are associated with greater transmission of CRE to HCP gloves and gowns in the hospital.

METHODS

This was a prospective observational cohort study that enrolled patients with recent surveillance or clinical cultures positive for CRE at five hospitals in four states in the USA. HCP gloves and gown were cultured after patient care. Samples were also obtained from patients' stool, perianal area, and skin of the chest and arm to assess bacterial burden.

FINDINGS

Among 313 CRE-colonized patients and 3070 glove and gown cultures obtained after patient care, HCP gloves and gowns were found to be contaminated with CRE 7.9% and 4.3% of the time, respectively. Contamination of either gloves or gowns occurred in 10.0% of interactions. Contamination was highest (15.3%) among respiratory therapists (odds ratio: 3.79; 95% confidence interval: 1.61-8.94) and when any HCP touched the patient (1.52; 1.10-2.12). Associations were also found between CRE transmission to HCP gloves or gown and: being in the intensive care unit, having a positive clinical culture, and increasing bacterial burden on the patient.

CONCLUSION

CRE transmission to HCP gloves and gown occurred frequently. These findings may inform evidence-based policies about what situations and for which patients contact precautions are most important.

Predictors of predominant Lupus Low Disease Activity State (LLDAS-50)

AIM

The Lupus Low Disease Activity State (LLDAS) is a potential treat to target goal in systemic lupus erythematosus (SLE). SLE patients in LLDAS for more than half of the observation time have about a 50% lower risk of new organ damage and have reduced mortality. We identified predictors of being in LLDAS ≥50% of the observation time.

METHODS

A total of 2228 SLE patients who had at least three clinical visits were included. Percentage of time in LLDAS was calculated based on the proportion of days under observation. LLDAS-50 was defined as being in LLDAS for ≥50% of the observation time. We used the stepwise selection procedure in logistic regression to identify predictors of LLDAS-50.

RESULTS

A total of 1169 (52.5%) SLE patients, but only 37.6% of African Americans, achieved LLDAS-50. In the multivariable model, African American ethnicity, hypocomplementemia, serositis, renal activity, arthritis, anti-RNP, anti-dsDNA, vasculitis, malar rash, discoid rash, thrombocytopenia, and immunosuppressive use were negative predictors of LLDAS-50. Older age at diagnosis, longer disease duration, higher education level, and greater percentage of time taking hydroxychloroquine remained positive predictors of LLDAS-50.

CONCLUSION

In this large cohort, only 52.5% achieved LLDAS-50. This proportion was even less in African Americans. A higher percentage of time taking hydroxychloroquine was a modifiable positive predictor of LLDAS-50. Anti-RNP, anti-dsDNA, and low complement were negatively associated with LLDAS-50. Our findings further emphasize the importance of inclusion of African Americans in clinical trials and hydroxychloroquine adherence in both clinical practice and clinical trials.

Serum osteoprotegrin (OPG) in subclinical atherosclerosis in systemic lupus erythematosus

Introduction Osteoprotegerin (OPG) is a member of the tumor necrosis factor (TNF) receptor family. It has recently been demonstrated that OPG is produced by a variety of tissues, including the cardiovascular system (heart, arteries, veins), lung, kidney, immune tissues, and bone. The OPG-RANKL signaling pathway is strongly related to vascular calcification. We determined the association of this biomarker with subclinical atherosclerosis in systemic lupus erythematous (SLE). Methods We measured OPG and markers of subclinical atherosclerosis (coronary artery calcium (CAC), carotid intima-media thickness (cIMT) carotid plaque) in 166 SLE patients (91% female, 64% Caucasian, 31% African American, 5% others, mean age 45 years). Subgroups of patients with different levels of OPG level were compared with respect to average levels of CAC, cIMT, and with respect to presence of carotid plaque. Age was adjusted for using multiple regression. Results OPG was highly correlated with age ( p < 0.0001). Individuals with higher levels of OPG tended to have higher measures of CAC, cIMT, and more carotid plaque. However, after adjustment for age, these associations, while still positive, were no longer statistically significant. Conclusion In our study much of the association observed was due to confounding by age, and after adjusting for age, our findings do not rule out the possibility of a null association.

Hydroxychloroquine use predicts complete renal remission within 12 months among patients treated with mycophenolate mofetil therapy for membranous lupus nephritis

The objective of this study was to identify clinical predictors of response to initial mycophenolate mofetil (MMF) therapy for membranous lupus nephritis (MLN). We observed the clinical outcomes of patients in the Hopkins Lupus Cohort within the first year of initiation of treatment with MMF therapy for newly diagnosed MLN, classified according to the new International Society of Nephrology/Renal Pathology Society (ISN/RPS) 2003 classification. Complete renal remission was defined as proteinuria less than 500 mg/24 hours. Demographic, clinical, treatment and laboratory data were examined for their association with renal remission. Twenty-nine MLN patients treated with MMF were identified. Eleven (38%) patients achieved complete renal remission by 12 months. Of those taking hydroxychloroquine, 7/11 (64%) were in remission within 12 months compared to only 4/18 (22%) of those not on hyroxychloroquine ( P 0.036 based on a log-rank test). This association persisted after controlling for the presence of anti-ds-DNA ( P 0.026). Our results provide evidence that hydroxychloroquine has a benefit for renal remission when MMF is used as the initial therapy for MLN. Although hydroxychloroquine is frequently stopped in patients with lupus nephritis, this study suggests it should be started or maintained.

Outcomes of living versus deceased donor liver transplantation for acute liver failure in the United States

Clinical outcomes for living donor liver transplantation (LDLT) for acute liver failure (ALF) in the United States remain to be determined. To address this gap in knowledge, we examined post-liver transplantation outcomes of adults with ALF undergoing LDLT and deceased donor liver transplantation (DDLT) in the United States. We analyzed Organ and Procurement and Transplantation Network data for adults with ALF who were listed for liver transplantation as status 1 or 1A and who underwent LDLT (N = 21) or DDLT (N = 2316) between October 1987 and April 2011. We found no strong evidence that the survival probabilities for adults with ALF who underwent LDLT were inferior to those who underwent DDLT (P = .764). In adults with ALF who underwent LDLT, 1- and 5-year survival probabilities were both 71%; for DDLT these probabilities were 79% and 71%, respectively. In adults with ALF, 1- and 5-year liver graft survival probabilities, respectively, were 62% and 57% for LDLT, and 74% and 66% for DDLT. In these series of adults with ALF who were listed as status 1 or 1A, patient and graft survival rates for LDLT were similar to those for DDLT. Our findings suggest that if deceased donor livers are unavailable, LDLT is an acceptable option in experienced centers for adults with ALF.

First-trimester prediction of pre-eclampsia: external validity of algorithms in a prospectively enrolled cohort

OBJECTIVE

To evaluate the performance of published first-trimester prediction algorithms for pre-eclampsia (PE) in a prospectively enrolled cohort of women.

METHOD

A MEDLINE search identified first-trimester screening-prediction algorithms for early-onset (requiring delivery < 34 weeks) and late-onset (requiring delivery ≥ 34 weeks) PE. Maternal variables, ultrasound parameters and biomarkers were determined prospectively in singleton pregnancies enrolled between 9 and 14 weeks. Prediction algorithms were applied to this population to calculate predicted probabilities for PE. The performance of the prediction algorithms was compared with that in the original publication and evaluated for factors explaining differences in prediction.

RESULTS

Six early and two late PE prediction algorithms were applicable to 871-2962 women, depending on the variables required. The prevalence of early PE was 1.0-1.2% and of late PE was 4.1-5.0% in these patient subsets. One early PE prediction algorithm performed better than in the original publication (80% detection rate (DR) of early PE for 10% false-positive rate (FPR)); the remaining five prediction algorithms underperformed (29-53% DR). Prediction algorithms for late PE also underperformed (18-31% DR, 10% FPR). Applying the screening cut-offs based on the highest Youden index probability scores correctly detected 40-80% of women developing early PE and 71-82% who developed late PE. Exclusion of patients on first-trimester aspirin resulted in DRs of 40-83% and 65-82% for early and late PE, respectively.

CONCLUSION

First-trimester prediction algorithms for PE share a high negative predictive value if applied to an external population but underperform in their ability to correctly identify women who develop PE. Further research is required to determine the factors responsible for the suboptimal external validity.

Anti-C1q antibodies in systemic lupus erythematosus

OBJECTIVE

Anti-C1q has been associated with systemic lupus erythematosus (SLE) and lupus nephritis in previous studies. We studied anti-C1q specificity for SLE (vs rheumatic disease controls) and the association with SLE manifestations in an international multicenter study.

METHODS

Information and blood samples were obtained in a cross-sectional study from patients with SLE (n = 308) and other rheumatologic diseases (n = 389) from 25 clinical sites (84% female, 68% Caucasian, 17% African descent, 8% Asian, 7% other). IgG anti-C1q against the collagen-like region was measured by ELISA.

RESULTS

Prevalence of anti-C1q was 28% (86/308) in patients with SLE and 13% (49/389) in controls (OR = 2.7, 95% CI: 1.8-4, p < 0.001). Anti-C1q was associated with proteinuria (OR = 3.0, 95% CI: 1.7-5.1, p < 0.001), red cell casts (OR = 2.6, 95% CI: 1.2-5.4, p = 0.015), anti-dsDNA (OR = 3.4, 95% CI: 1.9-6.1, p < 0.001) and anti-Smith (OR = 2.8, 95% CI: 1.5-5.0, p = 0.01). Anti-C1q was independently associated with renal involvement after adjustment for demographics, ANA, anti-dsDNA and low complement (OR = 2.3, 95% CI: 1.3-4.2, p < 0.01). Simultaneously positive anti-C1q, anti-dsDNA and low complement was strongly associated with renal involvement (OR = 14.9, 95% CI: 5.8-38.4, p < 0.01).

CONCLUSIONS

Anti-C1q was more common in patients with SLE and those of Asian race/ethnicity. We confirmed a significant association of anti-C1q with renal involvement, independent of demographics and other serologies. Anti-C1q in combination with anti-dsDNA and low complement was the strongest serological association with renal involvement. These data support the usefulness of anti-C1q in SLE, especially in lupus nephritis.

Oral candidiasis in systemic lupus erythematosus

OBJECTIVES

We assessed the frequency of oral candidiasis and the association between demographic variables, disease-related variables, corticosteroid treatment, other treatments and the occurrence of oral candidiasis in the Hopkins Lupus Cohort.

METHODS

In this large prospective cohort study of 2258 patients with systemic lupus erythematosus (SLE), demographic and clinical associates of oral candidiasis were estimated by univariate, multivariate and within-person regression models.

RESULTS

There were 53,548 cohort visits. Oral candidiasis was diagnosed at 675 visits (1.25%) in 325 (14%) of the patients. In the multivariate analyses, oral candidiasis was associated with African-American ethnicity, SELENA-SLEDAI disease activity, high white blood cell count, a history of bacterial infection, prednisone use and immunosuppressive use. The urine protein by urine dip stick was higher in SLE patients with oral candidiasis. Considering only patients who had candidiasis at some visits in a 'within-person' analysis, candidiasis was more frequent in visits with higher SELENA-SLEDAI disease activity, high white blood cell count, proteinuria by urine dip stick, a history of bacterial infection and prednisone use. The use of hydroxychloroquine was associated with a lower risk of oral candidiasis, but was not statistically significant (p = 0.50) in the within-person analysis models.

CONCLUSION

This study identified multiple risk factors for oral candidiasis in SLE. Inspection of the oral cavity for signs of oral candidiasis is recommended especially in SLE patients with active disease, proteinuria, high white blood cell count, taking prednisone, immunosuppressive drugs or antibiotics.

The American College of Rheumatology and the Systemic Lupus International Collaborating Clinics Classification criteria for systemic lupus erythematosus in two multiethnic cohorts: a commentary

The authors offer some comments on the advantages and possible drawbacks of using the SLICC criteria in longitudinal observational studies and clinical trials after applying and comparing them to the ACR criteria in two multinational, multiethnic lupus cohorts.

Predictors of corticosteroid tapering in SLE patients: the Hopkins Lupus Cohort

Purpose

Organ damage in systemic lupus erythematosus (SLE) patients is highly associated with the use of corticosteroids. Doses of prednisone below 6 mg daily are associated with reduced organ damage. We now report on the largest prospective cohort study of predictors of prednisone tapering in SLE patients.

Methods

A total of 866 SLE patients (91% female, 50% Caucasian, 43% African-American, mean age 43 years) who consented for the Hopkins Lupus Cohort from 1987 through 2009 were included. The analysis was based on patient visits in which the previously prescribed dose of prednisone was 5 mg/day. We then examined the proportion of times the patient’s dose was reduced to below 5 mg/day (“tapering”). Among those patients who tapered and were followed for at least one year thereafter, we examined the proportion whose prednisone dose remained below 5 mg/day for at least one year (“Successful tapering”). Rates of tapering and successful tapering were calculated for patient subsets based on demographic and clinical characteristics.

Result

The analyses showed that Caucasians, younger patients, patients with a higher level of education, lower disease activity, or absence of urine protein were more likely to have a prednisone taper. However, successful tapering was not dependent on age, ethnicity, or education. As expected, successful tapering was more frequent in those with lower disease activity. Successful tapering was achieved more often after the year 2000.

Conclusion

Our study suggests that successful tapering of prednisone below 5 mg has increased since the year 2000, which may reflect the greater knowledge of the long-term harm of even low-dose chronic corticosteroid use. Caucasians, younger age, higher level of education, and absence of proteinuria predicted tapering, but not successful tapering. Ongoing cutaneous or arthritis activity were associated with unsuccessful tapering. Lack of disease activity, as expected, was the only major clinical variable that significantly predicted successful tapering.

Simultaneous liver-kidney versus liver transplantation alone in patients with end-stage liver disease and kidney dysfunction not on dialysis

BACKGROUND

Since implementation of the Model for End-stage Liver Disease (MELD), the number of simultaneous liver-kidney transplantations (SLKT) has increased in the United States. However, predictors and survival benefit of SLKT compared to liver transplantation alone (LTA) are not well defined.

METHODS

Organ Procurement and Transplantation Network data of patients with end-stage liver disease (ESLD) with estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m(2) who had not been on dialysis while on the waiting list and underwent liver transplantation between 2002 and 2008 were analyzed. To identify predictors of undergoing SLKT versus LTA, multiple logistic regression analysis was performed. Cox proportional hazards regression analysis was used to assess the association between SLKT and post-liver transplant patient and graft survival.

RESULTS

The study cohort comprised 5443 patients; 262 (5%) underwent SLKT and 5181 (95%) underwent LTA. Adjusting for potential confounders, patients who underwent SLKT were 34% less likely to die after liver transplantation than those who underwent LTA (hazard ratio [HR] = 0.66, P = .012) and 33% less likely to have liver graft failure than those who underwent LTA (HR = 0.67, P = .010). Among those who underwent SLKT, 1-, 3-, and 5-year kidney graft survival probabilities were 88%, 80%, and 77%, respectively. Black race and diabetes were associated with a higher likelihood of SLKT versus LTA; female sex, a higher eGFR, and higher MELD score reduced the likelihood of SLKT.

CONCLUSIONS

Among those with ESLD and kidney dysfunction not on dialysis, post-liver transplant patient and liver graft survivals of patients who underwent SLKT were superior to those of patients who underwent LTA. Whether this reflects differences in the two groups that could not be adjusted in survival models or a specific effect of kidney dysfunction cannot be established.

Autoantibodies in systemic lupus erythematosus: comparison of historical and current assessment of seropositivity

Systemic lupus erythematosus (SLE) is characterized by multiple autoantibodies and complement activation. Recent studies have suggested that anti-nuclear antibody (ANA) positivity may disappear over time in some SLE patients. Anti-double-stranded DNA (dsDNA) antibody titers and complement levels may vary with time and immunosuppressive treatment, while the behavior of anti-extractable nuclear antigen (ENA) over time is less well understood. This study sought to determine the correlation between historical autoantibody tests and current testing in patients with SLE. Three hundred and two SLE patients from the ACR Reclassification of SLE (AROSE) database with both historical and current laboratory data were selected for analysis. The historical laboratory data were compared with the current autoantibody tests done at the reference laboratory and tested for agreement using percent agreement and Kappa statistic. Serologic tests included ANA, anti-dsDNA, anti-Smith, anti-ribonucleoprotein (RNP), anti-Ro, anti-La, rheumatoid factor (RF), C3 and C4. Among those historically negative for immunologic markers, a current assessment of the markers by the reference laboratory generally yielded a low percentage of additional positives (3-13%). However, 6/11 (55%) of those historically negative for ANA were positive by the reference laboratory, and the reference laboratory test also identified 20% more patients with anti-RNP and 18% more with RF. Among those historically positive for immunologic markers, the reference laboratory results were generally positive on the same laboratory test (range 57% to 97%). However, among those with a history of low C3 or C4, the current reference laboratory results indicated low C3 or C4 a low percentage of the time (18% and 39%, respectively). ANA positivity remained positive over time, in contrast to previous studies. Anti-Ro, La, RNP, Smith and anti-dsDNA antibodies had substantial agreement over time, while complement had less agreement. This variation could partially be explained by variability of the historical assays, which were done by local laboratories over varying periods of time. Variation in the results for complement, however, is more likely to be explained by response to treatment. These findings deserve consideration in the context of diagnosis and enrolment in clinical trials.

Dental care coverage transitions

OBJECTIVE

To examine dental insurance transition dynamics in the context of changing employment and retirement status.

STUDY DESIGN

Data from the Health and Retirement Study (HRS) were analyzed for individuals 51 years and older between the 2004 and 2006 waves of the HRS.

METHODS

The primary focus of the analysis is the relationship between retirement and transitions in dental care coverage. We calculate and present bivariate relationships between dental coverage and retirement status transitions over time and estimate a multivariable model of dental coverage controlling for retirement and other potentially confounding covariates.

RESULTS

Older adults are likely to lose their dental coverage on entering retirement compared with those who remain in the labor force between waves of the HRS. While more than half of those persons in the youngest group (51-64 years) were covered over this entire period, two-thirds of those in the oldest group (>or=75 years) were without coverage over the same period. We observe a high percentage of older persons flowing into and out of dental coverage over the period of our study, similar to flows into and out of poverty.

CONCLUSIONS

Dental insurance is an important factor in the decision to seek dental care. Yet, no dental coverage is provided by Medicare, which provides medical insurance for almost all Americans 65 years and older. This loss of coverage could lead to distortions in the timing of when to seek care, ultimately leading to worse oral and overall health.

Mycophenolate mofetil as the primary treatment of membranous lupus nephritis with and without concurrent proliferative disease: a retrospective study of 29 cases

Studies of immunosuppressive therapy, particularly mycophenolate mofetil (MMF), in membranous lupus nephritis (MLN) are limited. We report on our experience with primary (first-line) MMF therapy to induce and sustain renal remission in MLN with and without a concurrent proliferative lesion. Systemic lupus erythematosus (SLE) patients were studied, retrospectively, if treated with MMF for newly diagnosed MLN. Complete remission was defined as proteinuria less than 0.5 g/24 h, inactive urine sediment and normal estimated glomerular filtration rate. Response in pure MLN (Group I, n=10) was compared with mixed MLN and proliferative lupus nephritis (Group II, n=19). By 12 months, 4 (40%) patients in Group I and 7 (36.8%) in Group II achieved complete remission (P=0.87). One (10%) patient in Group I and 2 (10.5%) in Group II had worsening renal disease (P=0.97). Mean time to remission was more than seven months in both groups. The remaining patients had stable disease without improvement or worsening. Only 2 of 11 achieving initial remission had a relapse with an average of 28 months of follow-up after remission. Self-limited gastrointestinal symptoms occurred in 12 patients, none requiring withdrawal of the drug. Mycophenolate mofetil as a primary therapy in MLN was successful in inducing complete remission in about 40% of MLN, particularly in patients with mild proteinuria. However, 12 months of therapy was necessary for best outcomes. Response rate was not different in the presence or absence of a proliferative lesion.

Estimating renal function in lupus nephritis: comparison of the Modification of Diet in Renal Disease and Cockcroft Gault equations

Estimates of renal function are widely used in clinical practice and research. We assessed the performance of the Cockcroft-Gault (CG) and the Modification of Diet in Renal Disease (MDRD) equations in lupus nephritis patients. Data from ninety-seven lupus nephritis patients in the Hopkins Lupus Cohort were reviewed. Two renal function estimates, the CG and the MDRD, were compared with the 24 h creatinine clearance (CrCl). In the entire group of patients, the CG and MDRD equations had good global agreement with CrCl (R-square = 0.91 and 0.69, respectively). On average the CG equation overestimated CrCl by 2.36 mL/min/1.73 m(2), whereas the MDRD equation underestimated CrCl by 5.85 mL/min/1.73 m(2), P = 0.0004. The CG equation had greater accuracy (mean squared error) than the MDRD equation (14.93 versus 28.47 mL/min/1.73 m(2), P = 0.002) when predicting CrCl. Although both equations lacked precision (standard deviation of the difference scores) in patients with CrCl > or = 60 mL/min/1.73 m(2), the CG equation was more precise than the MDRD equation in this group, (15.68 versus 29.58 mL/min/1.73 m(2), P = 0.003). In lupus nephritis patients, the CG equation was superior to the MDRD equation as an estimate of CrCl. However, both equations lacked precision in patients with CrCl > or = 60 mL/min/1.73 m(2).

Predictors of high sensitivity C-reactive protein levels in patients with systemic lupus erythematosus

Despite the increased prevalence of cardiovascular disease in patients with systemic lupus erythematosus (SLE), little is known about the role of high sensitivity C-reactive protein (hsCRP) or whether ethnicity, gender, anthropometric measures and treatment can alter hsCRP levels. We evaluated the effects of treatment and demographic, anthropometric and socio-economic variables on hsCRP levels in SLE. High sensitivity C-reactive protein levels were measured using an immunoturbidimetric assay in 610 patients from the Hopkins Lupus Cohort, who were followed-up regularly. In stepwise multiple regression analyses, body mass index (BMI) [odds ratio (OR) 1.72, 95% confidence interval (CI) 1.34—2.20, P < 0.001], African-American ethnicity (OR 1.97, 95% CI 1.22—3.19, P < 0.01), education (OR 0.60, 95% CI 0.42—0.86, P < 0.01), statin use (OR 0.38, 95% CI 0.18—0.82, P < 0.05), estrogen use (OR 3.65, 95% CI 1.19—11.22, P < 0.05), SLE Disease Activity Index score (OR 1.76, 95% CI 1.09—2.87, P < 0.05) and cumulative prednisone dose (OR 1.27, 95% CI 1.01—1.60, P < 0.05) were significant predictors of hsCRP levels. These findings suggest that hsCRP levels should be adjusted for BMI, ethnicity, education level, disease activity and medications when conducting cardiovascular risk assessment in patients with lupus. Lupus (2008) 17, 114—123.

Randomised double-blinded trial evaluating silymarin for chronic hepatitis C in an Egyptian village: study description and 12-month results

BACKGROUND/AIMS

A double-blinded trial evaluating silymarin, an herbal supplement for liver disease, to prevent complications of chronic hepatitis C virus infection has not been done.

SUBJECTS

One hundred and seventy-seven consenting residents of an Egyptian village with chronic hepatitis C virus were randomly assigned to receive either silymarin or multivitamin supplements.

METHODS

Participants had baseline and follow-up clinical, ultrasound, blood tests and quality-of-life assessments. Community nurses visited weekly to ascertain compliance, distribute supplements and record adverse effects.

RESULTS

At 12 months almost all of 141 remaining subjects reported feeling better, although symptoms and quality-of-life scores did not differ between the silymarin and multivitamin groups. Both the silymarin and vitamins were tolerated equally well; and >95% of supplements were taken by >95% of subjects. One in each group had no detectable hepatitis C virus antibodies while two in the silymarin group and three receiving multivitamins had undetectable hepatitis C virus RNA. Serum alanine aminotransferase elevations did not differ between groups. Serum hepatic fibrosis marker, hyaluronic acid and YKL-40, and abdominal ultrasound results were similar in both groups and may have progressed slightly at 12 months.

CONCLUSIONS

The recommended dose of silymarin can be safely taken for 1 year and improves symptoms and general well-being, but has no effect upon hepatitis C virus viremia, serum ALT, or serum and ultrasound markers for hepatic fibrosis. More prolonged evaluation and a higher dose may be required to ascertain whether milk thistle supplements prevent complications of chronic hepatitis C virus.

Head growth and neurodevelopment of infants born to HIV-1-infected drug-using women

OBJECTIVE

To describe neurodevelopment and head growth in HIV-1-infected and exposed uninfected infants with and without in utero exposure to opiates and cocaine.

METHODS

Using data from a multicenter cohort study of HIV-1-infected women and their children, the authors fit repeated measures regression models to estimate the effects of HIV-1 infection and in utero hard drug exposure on head circumference and Bayley Scales of Infant Development standard scores during the first 30 months.

RESULTS

Of the 1,094 infants included in the analysis, 147 (13%) were HIV-1-positive and 383 (35%) were exposed in utero to opiates or cocaine (drug-positive). Mean 4- month Bayley mental scores were lower in infants with only HIV-1 positivity (HIV-positive and drug-negative) (-8.2 points, p < 0.0001) or only drug exposure (HIV-negative and drug-positive) (-4.4 points, p = 0.0001) and tended to be lower in infants with both factors (HIV-positive and drug-positive) (-3.7 points, p = 0.0596), compared with those who were HIV-1-negative and not drug exposed (HIV-negative and drug-negative). However, by 24 months of age, there was no longer a decrement among HIV-negative and drug-positive infants, whereas HIV-1 infection was still associated with a decrement relative to uninfected infants. Similar results were seen for Bayley motor scores and for head circumference Z scores.

CONCLUSIONS

HIV-1 infection and in utero opiate and cocaine exposure decrease birth head circumference and slow neurodevelopment at 4 months. At 24 months of age, however, only HIV-1 infection is associated with decreased neurodevelopment and head circumference. There may be some postnatal recovery from the effects of in utero hard drug exposure. Importantly, the detrimental effects of HIV-1 positivity and maternal hard drug use on neurodevelopment at 4 months are not additive, although they are additive for birth head circumference.

Decreases in anti-double-stranded DNA levels are associated with concurrent flares in patients with systemic lupus erythematosus

OBJECTIVE

To determine the degree to which changes in anti-double-stranded DNA (anti-dsDNA), as determined by Crithidia and enzyme-linked immunosorbent assays (ELISAs), precede or coincide with changes in systemic lupus erythematosus (SLE) activity, as measured by 5 clinical indices, the physician's global assessment (PGA), modified SLE Disease Activity Index (M-SLEDAI), modified Lupus Activity Index (M-LAI), Systemic Lupus Activity Measure (SLAM), and the modified British Isles Lupus Assessment Group (M-BILAG).

METHODS

Disease activity and anti-dsDNA were measured monthly in 53 SLE patients who were followed up for 1 year. Lupus flare was defined as an increase in PGA of > or = 1.0, M-SLEDAI > or = 3, M-LAI > or = 0.1, SLAM > or = 3, and M-BILAG > or = 4 within a 1-month period. Flare rates were calculated for groups, which were defined by "previous" (1 month prior to the flare) or "concurrent" (at the time of the flare) changes in anti-dsDNA. Logistic regression models were used to determine the significance of the association between recent changes in anti-dsDNA and flare, controlling for the prednisone dosage.

RESULTS

Flares occurred at 12% of visits, based on the PGA measure of disease activity. Using the other indices, flare rates were 19% (M-SLEDAI), 25% (M-LAI), 13% (SLAM), and 12% (M-BILAG). A concurrent decrease in anti-dsDNA (ELISA) was associated with significantly higher flare rates based on PGA (18 of 84, 21%; P = 0.0014), M-SLEDAI (27 of 89, 30%; P = 0.0019), M-LAI (37 of 89, 42%; P = 0.0001), and M-BILAG (19 of 89, 21%; P = 0.0264) scores. Flare rates were also significantly higher after a previous increase in anti-dsDNA (ELISA) based on M-SLEDAI (26 of 93, 30%; P = 0.0022) and M-LAI (34 of 93, 37%; P = 0.0117) scores. Flare rates tended to be lowest when there was a concurrent increase in anti-dsDNA (ELISA). Analysis of specific organ systems showed that a concurrent decrease in anti-dsDNA (ELISA) was significantly associated with increases in renal disease activity. Similar results were obtained using the Crithidia assay.

CONCLUSION

A previous increase in anti-dsDNA levels occurred before SLE flares, as measured by the M-SLEDAI and M-LAI only. However, during lupus flares, including the subset of renal flares, anti-dsDNA levels frequently decreased. We hypothesize that this decrease in anti-dsDNA represents deposition in tissue at the time of flare.

A decrease in complement is associated with increased renal and hematologic activity in patients with systemic lupus erythematosus

OBJECTIVE

To determine the degree to which changes in C3 and C4 precede or coincide with changes in systemic lupus erythematosus (SLE) activity, as measured by 5 global activity indices, the physician's global assessment (PGA), modified SLE Disease Activity Index (M-SLEDAI), modified Lupus Activity Index (M-LAI), Systemic Lupus Activity Measure (SLAM), and the modified British Isles Lupus Assessment Group (M-BILAG), and to evaluate the association between changes in C3 and C4 levels and SLE activity in individual organ systems.

METHODS

Fifty-three lupus patients were observed monthly for 1 year in a longitudinal study. Lupus disease activity and complement levels were measured at each visit. Lupus flare was defined as a 1.0 (or greater) increase in the PGA, a 3-point increase in the M-SLEDAI, a 0.1 increase in the M-LAI, a 3-point increase in the SLAM, or a 4-point increase in the M-BILAG within a 1-month period. Flare rates were calculated for subgroups defined by previous (1 month before) or concurrent changes in complement levels. Logistic regression models were used to determine the significance of the association between recent changes in complement levels and flare, controlling for prednisone dosage. Similar models were used to assess the association between changes in C3 or C4 levels and increased SLE activity in specific organ systems.

RESULTS

Lupus flares occurred at 12% of visits based on the PGA, 19% based on the M-SLEDAI, 25% based on the M-LAI, 13% based on the SLAM, and 12% based on the M-BILAG. Recent changes in C3 and C4 levels were not associated with flares based on 3 of the 5 activity indices. Flares defined by the M-LAI were more frequent when there was a concurrent decrease in C3 (odds ratio [OR] 1.9, 95% confidence interval [95% CI] 1.1-3.1) or C4 (OR 2.1, 95% CI 1.3-3.6). Higher flare rates, as defined by the SLAM, were associated with previous increases in C3 (OR 1.6, 95% CI 1.0-2.6) and C4 (OR 2.2, 95% CI 1.2-3.9). When individual organ systems were analyzed, decreases in C3 and C4 were associated with a concurrent increase in renal disease activity (OR 2.2, 95% CI 1.4-3.5 and OR 1.9, 95% CI 1.1-3.4, respectively). Decreases in C3 were also associated with concurrent decreases in the hematocrit (OR 4.6, 95% CI 1.7-12.3), platelet (OR 2.5, 95% CI 1.5-4.1), and white blood cell (OR 2.2, 95% CI 1.3-3.6) counts. Previous increases in C3 levels were associated with a decrease in platelets (OR 1.7, 95% CI 1.1-2.7). A decrease in C4 was associated with a concurrent decrease in the hematocrit level (OR 3.2, 95% CI 1.3-7.5) and platelet count (OR 1.6, 95% CI 1.0-2.5).

CONCLUSION

Decreases in complement levels were not consistently associated with SLE flares, as defined by global measures of disease activity. However, decreasing complement was associated with a concurrent increase in renal and hematologic SLE activity.

Epidemiologic usefulness of spoligotyping for secondary typing of Mycobacterium tuberculosis isolates with low copy numbers of IS6110

Restriction fragment length polymorphism (RFLP) analysis of IS6110 is commonly used to DNA fingerprint Mycobacterium tuberculosis. However, low-copy (< or =5) IS6110 M. tuberculosis strains are poorly differentiated, requiring secondary typing. When spoligotyping was used as the secondary method, only 13% of Maryland culture-positive tuberculosis (TB) patients with low-copy IS6110-spoligotyped clustered strains had epidemiologic linkages to another patient, compared to 48% of those with high-copy strains clustered by IS6110 alone (P < 0.01). Spoligotyping did not improve a population-based molecular epidemiologic study of recent TB transmission.

Serotype distribution of Salmonella isolates from food animals after slaughter differs from that of isolates found in humans

If raw meat and poultry are the primary point of entry for Salmonella species into human populations, a correlation might be expected between the serotype distribution of Salmonella species isolated from animals at the time of slaughter and that of isolates found in humans. For 1990-1996, sufficient national data were available to permit such a comparison. A mathematical model was developed to predict serotype distributions of Salmonella isolates among humans on the basis of animal data. There was a significant mismatch between the serotype distributions among humans predicted by the model and those actually observed. This mismatch raises questions about the validity of the "standard" assumptions about Salmonella transmission on which the model was based-namely, that raw animal products are the primary source for human salmonellosis, that the risk of transmission to humans is equal for all food product categories, and that all Salmonella serotypes have an equal ability to cause human illness.

Hepatitis C virus infection in a community in the Nile Delta: risk factors for seropositivity

The purpose of this study was to identify risk factors for hepatitis C virus (HCV) infection in a rural village in the Nile Delta with a high prevalence of antibodies to HCV (anti-HCV). One half of the village households were systematically selected, tested for anti-HCV, and interviewed: 973 of 3,999 (24.3%) subjects were anti-HCV-positive (reflecting prior HCV infection but not necessarily current liver disease), with nearly equal prevalence among males and females. Anti-HCV prevalence increased sharply with age among both males and females, from 9.3% in those 20 years of age and younger to >50% in those older than 35, suggesting a cohort effect with reduced transmission in recent years. Multivariate regression was used to estimate independent effects of risk factors on seropositivity. Among those over 20 years of age, the following risk factors were significantly associated with seropositivity: age (P <.001); male gender (odds ratio [OR] = 2.5, 95% CI = 1.3-4.7); marriage (OR = 4.1, 2.4-6.9); anti-schistosomiasis injection treatment (OR = 2.0, 1.3-2.9); blood transfusion (OR = 1.8, 1.1-2.9), invasive medical procedure (surgery, catheterization, endoscopy, and/or dialysis) (OR = 1.5, 1.1-1.9); receipt of injections from "informal" health care provider (OR = 1.3, 1.0-1.6); and cesarean section or abortion (OR = 1.4, 1.0-1.9). Exposures not significantly related to anti-HCV positivity in adults included: history of, or active infection with, Schistosoma mansoni, sutures or abscess drainage, goza smoking in a group, and shaving by community barbers. Among those 20 years old or younger, no risk factors were clearly associated with anti-HCV positivity; however, circumcision for boys by informal health care providers was marginally associated with anti-HCV (OR = 1.7, 1.0-3.0). Prevention programs focused primarily on culturally influenced risks in rural Egyptian communities are being implemented and evaluated.

Cost effectiveness of abciximab during routine medical practice

OBJECTIVE

To estimate the cost per ischaemic event (death, nonfatal myocardial infarction, subsequent revascularisation procedure) avoided at 6 months in high risk patients undergoing coronary revascularisation treated with abciximab during routine medical care.

DESIGN

Retrospective, matched cohort design.

SETTING

University teaching hospital.

PATIENTS

62 abciximab-treated patients and 62 patients not treated with abciximab with high risk coronary lesions were matched according to gender, hyperlipidaemia, diabetes mellitus and stenting.

MAIN OUTCOME MEASURES

Using a third-party payer's perspective, an incremental cost-effectiveness ratio (ICER) was computed as the cost per ischaemic event avoided over 6 months. Fieller's theorem was used to estimate confidence sets and confidence ellipses were generated to visually represent the variability in the data.

RESULTS

At 6 months, abciximab-treated patients experienced an approximately 40% lower rate of ischaemic events (16.1 vs 27.4%; p = 0.128). The point estimate of the ICER was $US21,789 per ischaemic event avoided. Fieller's theorem resulted in a 95% confidence set consisting of 2 half-lines (-infinity to -$US115,461) and ($US391 to +infinity), reflecting the finding that the ICER denominator was not significantly different from zero at the p = 0.05 level.

CONCLUSIONS

In high risk patients treated during routine care, the effectiveness of abciximab was consistent with efficacy rates from clinical trials. However, abciximab-treated patients remained approximately $US2400 more costly at 6 months.

Damage in systemic lupus erythematosus and its association with corticosteroids

OBJECTIVE

To evaluate the association between corticosteroid use and organ damage in patients with systemic lupus erythematosus (SLE).

METHODS

The occurrence and date of organ damage, as measured by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index, were determined for 539 patients enrolled in the Hopkins Lupus Cohort Study. The risk of damage associated with the cumulative prednisone dose, high-dose prednisone (> or =60 mg/day for > or =2 months), and pulse methylprednisolone (1,000 mg intravenously for 1-3 days) was estimated using Cox proportional hazards regression analyses, controlling for age, race, and sex. Risk estimates for the cumulative prednisone dose were based on a reference dose of 36.5 gm (e.g., 10 mg of prednisone daily for 10 years [or equivalent]).

RESULTS

The cumulative prednisone dose was significantly associated with the development of osteoporotic fractures (relative risk [RR] 2.5, 95% confidence interval [95% CI] 1.7, 3.7), symptomatic coronary artery disease (RR 1.7, 95% CI 1.1, 2.5), and cataracts (RR 1.9, 95% CI 1.4, 2.5). Each intravenous pulse was associated with a small increase in the risk of osteoporotic fractures (RR 1.3, 95% CI 1.0, 1.8); however, this result failed to reach statistical significance (P = 0.07). Each 2-month exposure to high-dose prednisone was associated with a 1.2-fold increase in the risk of both avascular necrosis (95% CI 1.1, 1.4) and stroke (95% CI 1.0, 1.5).

CONCLUSION

SLE patients receiving long-term prednisone therapy were at significant risk of morbidity due to permanent organ damage. Additional research is required to determine the relative contributions of SLE disease activity and corticosteroids to the pathogenesis of specific types of organ damage. Furthermore, new steroid-sparing therapies are needed in order to treat disease activity and minimize cumulative and high-dose prednisone exposure.

The role of parenteral antischistosomal therapy in the spread of hepatitis C virus in Egypt

BACKGROUND

The population of Egypt has a heavy burden of liver disease, mostly due to chronic infection with hepatitis C virus (HCV). Overall prevalence of antibody to HCV in the general population is around 15-20%. The risk factor for HCV transmission that specifically sets Egypt apart from other countries is a personal history of parenteral antischistosomal therapy (PAT). A review of the Egyptian PAT mass-treatment campaigns, discontinued only in the 1980s, show a very high potential for transmission of blood-borne pathogens. We examine the relative importance of PAT in the spread of HCV in Egypt.

METHODS

The degree of exposure to PAT by cohort was estimated from 1961-86 Ministry of Health data. A cohort-specific exposure index for PAT was calculated and compared with cohort-specific HCV prevalence rates in four regions.

FINDINGS

HCV prevalence was calculated for 8499 Egyptians aged 10-50 years. A significant association between seroprevalence of antibodies to HCV and the exposure index (1.31 [95% CI 1.08-1.59]; p=0.007) was identified across four different regions. In all regions cohort-specific HCV prevalence was lowest in children and young adults than in older cohorts. These lower prevalence rates coincided with the gradual and final replacement of PAT with oral antischistosomal drugs at different points in time in the four regions.

INTERPRETATION

The data suggest that PAT had a major role in the spread of HCV throughout Egypt. This intensive transmission established a large reservoir of chronic HCV infection, responsible for the high prevalence of HCV infection and current high rates of transmission. Egypt's mass campaigns of PAT may represent the world's largest iatrogenic transmission of blood-borne pathogens.

Association of coping responses with fibromyalgia tender points in patients with systemic lupus erythematosus

OBJECTIVE

To determine the association between fibromyalgia (FM) tender points (TP) and psychological constructs in patients with systemic lupus erythematosus (SLE).

METHODS

One hundred seventy-three patients with SLE were examined for FM TP, and asked to complete 2 questionnaires at the same visit, the Health-Related Hardiness Scale (HRHS), and the Mishel Uncertainty in Illness Scale (MUIS).

RESULTS

The examination of FM TP showed that 38.2% had no TP, 44.5% had 1-10 TP, and 17.3% had > or = 11 TP. The mean +/- SD score of the HRHS was 155.6 +/- 19.7 (range 105.0-198.0; higher scores indicate greater hardiness), and the MUIS was 85.3 +/- 18.7 (range 41.0-132.0; higher scores indicate uncertainty). There were significant associations between FM TP and HRHS (no TP 161.2 +/- 20.2, 1-10 TP 152.5 +/- 19.7, > or = 11 TP 151.0 +/- 15.8; p = 0.0108) and between FM TP and MUIS (no TP 78.2 +/- 20.2, 1-10 TP 86.9 +/- 17.6, > or = 11 TP 95.8 +/- 14.7; p = 0.0001).

CONCLUSION

This study shows a strong association between FM TP and uncertainty or lack of "hardiness." We conclude that SLE patients with FM TP are less likely to be good "copers." Prospective studies to determine if "poor coping" predicts FM in SLE are recommended. If the association between coping and FM is causal, it will justify interventions to improve coping and similar constructs, such as self-efficacy.

Utilization of multiple imperfect assessments of the dependent variable in a logistic regression analysis

Often, in biomedical research, there are multiple sources of imperfect information regarding a dichotomous variable of interest. For example, in a study we are conducting on the relationship between cocaine use and stroke risk, information on the cocaine use of each study patient is available from three fallible sources: patient interviews; urine toxicology testing, and medical record review. Regression analyses based on a rule for classifying patients from this information can result in biased estimation of associations and variances due to the misclassification of some subjects and to the assumption of certainty. We describe a likelihood-based method that directly incorporates multiple sources of information regarding an outcome variable into a regression analysis and takes into account the uncertainty in the classification. The method can be applied when some sources of information are missing for some subjects. We show how the availability of multiple sources can be exploited to generate estimates of the quality (for example, sensitivity and specificity) of each source and to model the degree to which missing data are informative. A fitting algorithm and issues of identifiability are discussed. We illustrate the method using data from our study.

Psychotherapeutic medication patterns for youths with attention-deficit/hyperactivity disorder

OBJECTIVES

(1) To describe temporal patterns of office visits for attention-deficit/hyperactivity disorder (ADHD) and stimulant treatment for 5- to 14-year-old US youths; (2) to compare youth visits for ADHD with and without melication according to patient demographics, physician specialty, reimbursement source, and comorbid diagnoses; and (3) to compare office visits for youths with ADHD in relation to common medication patterns (stimulants alone, stimulants with other psychotherapeutic medication, and nonstimulant psychotherapeutic medications alone).

DESIGN

Survey based on a national probability sample of office-based physicians in the United States.

SETTING

Physician offices.

PARTICIPANTS

A systematically sampled group of office-based physicians.

MAIN OUTCOME MEASURES

National estimates of office visits for ADHD and psychotherapeutic drug visits for ADHD for each year and for a combined 8-year period.

RESULTS

Youth visits for ADHD as a percentage of total physician visits had a 90% increase, from 1.9% in 1989 to 3.6% in 1996. Stimulant therapy within ADHD youth visits rose from 62.6% in 1989 to 76.6% in 1996. While the majority of non-ADHD youth visits were conducted by primary care physicians, one third of ADHD youth visits were managed by psychiatry and neurology specialists. Health maintenance organization insurance was the reimbursement source for 17.9% of non-ADHD youth visits but only 11.7% of ADHD youth visits. Complex medication therapy was more likely to be prescribed by psychiatrists and less likely to be related to visits with health maintenance organization reimbursement.

CONCLUSIONS

National survey estimates in the 1990s confirm the substantial increase in visits for youths diagnosed as having ADHD, with more than three quarters of these visits associated with psychotherapeutic medication treatment. Physician specialty and reimbursement source variables identify distinct patient populations with a gradient in psychotherapeutic medication patterns from single-drug standard (stimulant) therapy to complex multidrug treatment regimens for which evidence-based scientific information is lacking.

Patterns of disease activity in systemic lupus erythematosus

OBJECTIVE

To describe patterns of systemic lupus (SLE) disease activity over time.

METHODS

Disease activity was measured in a prospective cohort of 204 consecutive SLE patients followed up quarterly for 2.0-7.5 years (911 person-years of followup). Physician's global assessment (PGA) and modified SLE Disease Activity Index (M-SLEDAI; omitting serology) scores were plotted against time for each patient. Definitions for disease activity patterns were developed by consensus using these plots, and the proportion of total follow-up time represented by each pattern was calculated.

RESULTS

Three patterns of SLE activity were apparent: relapsing-remitting (RR), chronic active (CA), and long quiescent (LQ). The CA pattern was the most frequent for both the PGA and M-SLEDAI, representing 58% and 40% of total person-years, respectively. The least common pattern was LQ (PGA 16%, M-SLEDAI 25%), while the RR pattern was intermediate in frequency (PGA 26%, M-SLEDAI 35%). Average disease activity during RR periods tended to be mild, while that during CA periods was more likely to be moderately severe. The most common discrepancy between instruments was that the PGA depicted CA when the M-SLEDAI showed an RR pattern. The M-SLEDAI did not appear to capture mild degrees of activity.

CONCLUSION

SLE activity was readily classified into 1 of 3 patterns: RR, CA, or LQ. The CA pattern was most common, suggesting that significant morbidity may arise from persistent disease activity. These findings may have important implications regarding the choice of outcome measures in SLE clinical trials, since comparison of flare rates may not account for chronic disease activity.

Evidence for an across-frequency, between-channel process in asymptotic monaural temporal gap detection

Monaurally measured temporal gap detection (TGD) thresholds characteristically increase as the frequency difference is increased over a range of about half an octave to an octave between two sinusoids that mark the onset and offset of the silent gap. For greater sinusoidal frequency separations, the TGD thresholds often become asymptotic. This pattern probably reflects two different processes. The first process likely reflects within-channel processing within a single auditory filter or channel. The second process is less certain, but may reflect between-channel processing of the silent gap stimulus across two or more independent frequency channels. To evaluate the hypothesis that asymptotic monaural gap detection can be explained by a simple between-channel process, TGD thresholds were measured as a function of frequency separation between a pregap sinusoid presented to the left ear (channel 1) and a postgap sinusoid, of higher frequency, presented to the right ear (channel 2). The rationale for dichotic presentation of the sinusoidal markers and gap signal followed from the fact that the gap detection task must be performed between two independent channels by combining the outputs from each channel (ear) and recovering the gap information centrally. The resulting TGD thresholds for pregap sinusoids from 250 to 4000 Hz were relatively invariant and increased only slightly with increasing marker frequency separation. The average TGD thresholds for four listeners were in the range of 30 to 40 ms, which corresponded closely with their asymptotic TGD thresholds for the same set of stimulus conditions measured monaurally. This correspondence of the two data sets supports an across-frequency, between-channel process for asymptotic monaural gap detection at marker frequency separations greater than about half an octave.

Demographic and socioeconomic predictors of dental care utilization

The authors analyzed a comprehensive, nationally representative data set from the 1989 National Health Interview Survey to determine what factors are related to dental care utilization. The authors estimated the percentage of low-income and minority adults who reported visiting a dentist in the past year by race, income, employment status, dental insurance coverage status, sex, health status, education, marital status, age and major activity. Data analyses focused on 49,687 18- to 64-year-old dentate respondents, who were black, Hispanic or white. The authors found large differences in dental care utilization between blacks, Hispanics and whites, when controlling for education, income, age and other variables.

Evaluation of 14- and 11-gauge directional, vacuum-assisted biopsy probes and 14-gauge biopsy guns in a breast parenchymal model

PURPOSE

To compare commercially available 14-guage core biopsy guns and 11- and 14-gauge, directional, vaccum-assisted biopsy probes for tissue yield and fragmentation.

MATERIALS AND METHODS

One hundred passes were made through fresh turkey breasts by using each of 11 14-gauge, automated biopsy gun-needle combinations and a directional, stereotactic, vacuum-assisted biopsy system equipped with 11- or 14-gauge probes. Specimens were measured for total weight, individual length, diameter, and number of fragments.

RESULTS

Among the handheld devices, the Pro-Mag 2.2 gun (Manan Medical Products, Northbrook, Ill) and 14-gauge Biopsy-Cut needle (Bard, Covington, Ga) had the greatest yield (17.7 mg per core specimen); this combination also produced the greatest percentage of nonfragmented cores (83%). Directional, vacuum-assisted biopsy specimens were significantly larger (P < .001): 36.8 mg per core specimen for the 14-gauge probe and 94.4 mg per core specimen for the 11-gauge probe. Specimens obtained with directional, vacuum-assisted biopsy were more fragmented than those obtained with spring-actuated, two-stage, long-throw, automated biopsy systems.

CONCLUSION

Statistically significant differences with various biopsy devices are seen in the breast tissue yield and in fragmentation.

Logistic regression when the outcome is measured with uncertainty

In epidemiologic research, logistic regression is often used to estimate the odds of some outcome of interest as a function of predictors. However, in some datasets, the outcome of interest is measured with imperfect sensitivity and specificity. It is well known that the misclassification induced by such an imperfect diagnostic test will lead to biased estimates of the odds ratios and their variances. In this paper, the authors show that when the sensitivity and specificity of a diagnostic test are known, it is straightforward to incorporate this information into the fitting of logistic regression models. An EM algorithm that produces unbiased estimates of the odds ratios and their variances is described. The resulting odds ratio estimates tend to be farther from the null but have greater variance than estimates found by ignoring the imperfections of the test. The method can be extended to the situation where the sensitivity and specificity differ for different study subjects, i.e., nondifferential misclassification. The method is useful even when the sensitivity and specificity are not known, as a way to see the degree to which various assumptions about sensitivity and specificity affect one's estimates. The method can also be used to estimate sensitivity and specificity under certain assumptions or when a validation subsample is available. Several examples are provided to compare the results of this method with those obtained by standard logistic regression. A SAS macro that implements the method is available on the World Wide Web at http:@som1.ab.umd.edu/Epidemiology/software.h tml.

Methylphenidate patterns among Medicaid youths

Treatment of attentional disorders in America has increased dramatically in recent years. This trend is accounted for partly by lengthening the duration of treatment into adulthood for some individuals as well as by increased treatment among girls. Beyond these factors, the role of economic status, race, and geographic region to explain the variation in methylphenidate use is not well understood. Computerized administrative data were used to explore the influence of several sociodemographic factors on the prevalence of methylphenidate use. The data source consisted of Maryland Medicaid prescription drug reimbursement claims data for FY1991 for children ages 5 to 14 years. In effect, the study was restricted to a sample of patients with limited income. The study aims included (1) measuring gender-, age-, race-, and region-specific methylphenidate prevalence for this restricted income population; (2) comparing the Caucasian:African-American (C:A-A) ratio for methylphenidate with the C:A-A ratio for several drug therapies having non-psychotropic uses, specifically the anti-asthma drug, theophylline, and antibiotics for infections; and (3) estimating the average daily dose of methylphenidate from prescription claims data. Total drug-specific prevalence among the 5-14 year olds was 2.2 percent for methylphenidate while age-specific prevalence varied from 0.4 percent (5 year olds) to 3.4 percent (9 year olds). The gender ratio was 3.7:1 (M:F), confirming the increasing trend for girls to receive this medication. Substantial variation across eight defined regions of the state was observed. Racial differences were pronounced: African-Americans were 2.5 times less likely to receive methylphenidate than Caucasian youths. As hypothesized, non-psychotropic drug use was distinctly different from psychotropic drug use in terms of race: theophylline was 1.5 times more likely to be found for African-Americans than Caucasians, whereas antibiotic prescriptions were 1.5 times more likely to be prescribed to Caucasian youths. Average daily dose of methylphenidate was estimated to be 18.7 +/- 10.4 mg for 5-9 year olds and 26.8 +/- 14.0 mg for 10-14 year olds. This brief report confirms the typically lower rate among African-American Medicaid youths for most prescription drugs. The dramatic racial disparity for the psychotropic agent methylphenidate is a new and compelling finding which should be verified among other economic groups. Diagnostic, referral, and cultural bias should be ruled out as possible explanations for the observed differences.

Large-core biopsy guns: comparison for yield of breast tissue

PURPOSE

To compare seven large-core, long-throw, 14-gauge biopsy guns for yield and quality of breast tissue obtained.

MATERIALS AND METHODS

A two-phase, randomized and blinded study was performed. In the first phase, four fully automated 14-gauge biopsy guns (BIP, Manan, Biopsy, and ASAP) and one semiautomated device (Temno) were used to obtain breast cores from a cadaver. Samples were assessed for volume, number of fragments, and crush artifact. In the second phase, seven biopsy guns (previously mentioned guns plus Monopty and Ultra-Cut guns) were used to obtain cores from a breast parenchyma model. These cores were then evaluated for weight, volume, and number of fragments.

RESULTS

The mean specimen volume of cadaveric breast tissue obtained was 17.9 mm3 for the BIP gun, 17.8 for the Manan gun, 14.9 for the Biopsy gun, 14.1 for the ASAP gun, and 9.9 for the Temno gun. The Temno gun obtained statistically significantly smaller volumes than all other guns. For the breast parenchyma model, mean obtained volumes were 24.5, 24.1, 16.2, 21.7, 17.5, 20.0, and 15.2 mm3, respectively. The BIP and Manan guns yielded statistically significantly larger cores than all other guns except the ASAP.

CONCLUSION

Yields of breast tissue provided by each biopsy device differed statistically significantly. BIP and Manan biopsy guns yielded the greatest volume of core tissue, which may facilitate histopathologic diagnosis from breast biopsies performed with imaging guidance.

Isocaloric glutamine-free diet and the morphology and function of rat small intestine

BACKGROUND

The importance of L-glutamine as metabolic fuel for enterocytes and its role in prevention of mucosal atrophy during total parenteral nutrition is well documented. No data are available to date that document whether a glutamine-free complete enteral diet, requiring full energy expenditure for hydrolysis and absorption, is associated with changes in the morphology and function of the small intestine. Our aim was to examine the effect of such a diet during a 4-week period on the morphology and function of the small intestine of rats.

METHODS

Three isocaloric solid rat food, containing 0%, 4%, and 8% of glutamate, respectively, were fed to three groups of rats. On the 7th and 28th days the morphology of the jejunum, the subcellular structure of enterocytes on transmission electron microscopy, enzyme activities, blood, and muscle glutamine were examined and compared in the three groups.

RESULTS

The rats on the glutamine-free diet had significantly lower mucosal wet weight, protein and DNA content, and number of intraepithelial lymphocytes on the 7th day, whereas the number of mitoses in the Lieberkuhn's crypts was significantly less on the 28th day. The height of the enterocytes and villi was 20% higher on average in the glutamine-free group. Electron microscopy revealed either early (swelling of cristae) or terminal (swelling of matrix) mitochondrial degenerative changes, homogenization of apical cytoplasm, and degeneration and fragmentation of microvilli with loss of their rootlets. The Na+, K(+)-ATPase activity was markedly decreased in the glutamine-free group compared with that of the other groups, most likely because of a diminished energy supply. Among brush border membrane enzymes, lactase activity decreased markedly (p < .05) in the first week. The glutamine-free diet resulted in an increase of the lung glutamine synthetase activity and decrease in muscle glutamine content by the 28th day of the diet.

CONCLUSIONS

Our study shows for the first time that a complete enteral diet, deficient only in glutamine, is associated with significant early morphologic and functional changes in the small intestine. The precise effect on intracellular events and the time of onset of these changes needs to be clarified in the future.

Condom use with regular and casual partners among women attending family planning clinics

A survey of 16,632 women attending family planning clinics in Pennsylvania found that only 13 percent of the sample used condoms. Moreover, 67 percent of the women with regular partners never used condoms with those partners, and 72 percent of women who had casual partners never used them with those partners. Levels of condom use with both regular and casual partners were higher among women younger than 20, those who were nonwhite, those with multiple partners and those who reported a previous STD infection. However, women who had sex partners who used intravenous drugs were less likely to use condoms with regular or casual partners than were women who did not have drug-using partners.

Effect of patient characteristics on performance of an enzyme immunoassay for detecting cervical Chlamydia trachomatis infection

We compared the performance of a commercial enzyme immunoassay (EIA) (Chlamydiazyme; Abbott Diagnostics, North Chicago, Ill.) with that of cell culture for the detection of Chlamydia trachomatis cervical infection in 1,417 women attending public health clinics. Confirmatory chlamydial testing by a direct fluorescent-antibody test (MicroTrak; Syva Co., Palo Alto, Calif.) was performed on specimens from women who had positive EIAs. Overall, only 57% of women who had a positive chlamydial test by cell culture were also positive by EIA. We noted a strong association between the number of chlamydial inclusions in cell culture and a positive EIA outcome. The proportion of culture-positive women who also had a positive EIA declined with age and a history of previous sexually transmitted disease and increased among oral contraceptive users. The results of direct fluorescent-antibody confirmatory testing suggested that cell culture was also insensitive for the detection of C. trachomatis infection. Our observations demonstrate that the performance of the chlamydial EIA may vary greatly with individual patient characteristics and that the utility of EIA as a screening test may be limited, especially in older women.

Risk behaviors for HIV infection in clients of Pennsylvania family planning clinics

Responses from a statewide survey of risk behaviors among clients of Planned Parenthood clinics in Pennsylvania indicate that a sizable proportion of these women are at intermediate or high risk for exposure to the human immunodeficiency virus (HIV). Overall, nearly five percent of the 15,499 women in the sample reported personal behavior, or a partner's behavior, that placed them at high risk, while an additional 20 percent were at intermediate risk. Among all women surveyed, 13 percent had had three or more partners in the past year, 12 percent had had a sexually transmitted disease, four percent had partners who were intravenous (IV) drug users, two percent were either current or past IV drug users, one percent had bisexual partners and less than one percent had partners who had hemophilia or who were infected with the AIDS virus.

A seroepidemiologic survey of the prevalence of herpes simplex virus type 2 infection in the United States

The prevalence of infection with the genital herpes simplex virus type 2 (HSV-2) has been difficult to ascertain, primarily because of the large percentage of subclinical cases and the limitations in specificity of serologic assays for antibody to HSV-2. To obtain an improved estimate of the distribution of HSV-2 infection in the United States, we used an HSV type-specific antibody assay to test serum samples from 4201 participants in the second National Health and Nutrition Examination Survey. The results in our sample indicate that in the period from 1976 to 1980, 16.4 percent of the U.S. population 15 to 74 years of age (approximately 25 million persons) was infected with HSV-2 (95 percent confidence interval, 14.2 to 18.6 percent). Age and race were the demographic factors associated most strongly with the presence of HSV-2 antibody. The prevalence of the antibody increased from less than 1 percent in the group under 15 years old to 20.2 percent in the group 30 to 44 years old; it increased only slightly thereafter. In the oldest group, 60 to 74 years of age, the prevalence was 19.7 percent in whites and 64.7 percent in blacks. Among blacks of all age groups, but not whites, higher rates were observed in women than in men. The associations were weaker with respect to marital status, income, education, urban residence, and region of the country. After control for age, sex, and race, only the association with marital status remained significant; the rate was increased in persons previously married--i.e., divorced, separated, or widowed. We conclude that the prevalence of HSV-2 infection in the United States is higher than has previously been recognized and that many infections with this sexually transmitted virus may be subclinical.

Race and the prevalence of syphilis seroreactivity in the United States population: a national sero-epidemiologic study

We used the 1978 National Health and Nutrition Examination Survey to examine the prevalence of positive syphilis serologies in the US population. Analysis of risk markers--gender, age, marital status, education, income, and residence--indicates that all except gender are associated with syphilis seroreactivity, independent of race. Controlling for associated risk markers, the Black-White odds ratio of syphilis seroreactivity is 4.7 (95% CI = 2.7, 8.2). Current knowledge of racial differences in sexual and health care behavior does not explain the Black-White difference in the prevalence of syphilis seroreactivity.

Factors related to genital Chlamydia trachomatis and its diagnosis by culture in a sexually transmitted disease clinic

The authors cultured 2,320 patients who attended the Denver Metro Health Clinic for Sexually Transmitted Diseases from September 1981 to June 1983 to determine clinical and epidemiologic factors associated with genital chlamydial infection. Among consecutive heterosexual men with urethral discharge, 226 of 849 (27%) had positive urethral cultures, with rates significantly lower among those with profuse (18%) or purulent (19%) discharges, and higher (37%) among those with symptoms for more than seven days. In a subgroup of men without gonococci, those who had polymorphonuclear leukocytes on smear had higher isolation rates (33%) than those who did not (3%). Among consecutive female patients, 172 of 1,031 (17%) had positive cervical cultures, with rates significantly lower in those who were white (13%), married (7%), or using a diaphragm (0 of 77), and higher in those who were positive for Neisseria gonorrhoeae (38%). There was a marginally significant increased rate of chlamydial isolation among oral contraceptive users only for women aged 20 years or younger. Younger age was significantly associated with chlamydial isolation in both men and women after controlling for sexual activity and other factors. Various patient characteristics can be combined to define subgroups of men and women, with rates of isolation ranging from under 4% to over 60%. These results can be useful in deciding whom to test and whom to treat presumptively in a public health setting.

Acute Chlamydia trachomatis respiratory infection in childhood. Serologic evidence

Serum samples from 184 infants and children whose blood was drawn during a clinic visit were tested for antibody to Chlamydia trachomatis, Epstein-Barr virus, and cytomegalovirus. Lifetime illness history was obtained from clinic records. Fifteen percent had anti-C trachomatis IgM antibody. Anti-C trachomatis IgM without IgG was significantly associated with upper respiratory tract syndromes within the 14 days prior to phlebotomy in 6- to 10-year-old patients. This association was not due to polyclonal activation from Epstein-Barr virus infection. A definitive study of chlamydial illness in children rather than infants appears to be indicated.

Personal protection against sexually transmitted diseases

Primary prevention of sexually transmitted diseases has received little emphasis in control programs. To evaluate the effectiveness of prevention strategies, we reviewed the world's literature on this topic. Use of condoms and spermicides greatly reduces the risk of gonorrhea, and barrier methods are practical and acceptable. Certain systemic antibiotics are effective, but for practical reasons, their use cannot be recommended. Washing or urinating after sexual exposure does not appear to protect against infection. Although the effectiveness of modifying sexual behavior to reduce the risk of sexually transmitted diseases has not been evaluated, many people have changed or are willing to change their behavior. Even if preventive measures are used consistently by only a minority of persons at risk, rates of sexually transmitted diseases would decline rapidly. In this era of sexually transmitted diseases that are not readily cured by antibiotics, use of effective preventive measures should be strongly encouraged.

Primary prevention of sexually transmitted diseases. A primer for clinicians

With the advent of sexually transmitted infections for which curative therapy is not available, primary prevention has assumed greater importance. The spectrum of sexually transmitted diseases (STDs) has broadened, and clinicians need to understand the mechanisms of their transmission and prevention. Modifying selection of sexual partners and avoiding certain sexual practices should theoretically reduce the risk of infection. Clinical and laboratory studies indicate that the use of condoms, diaphragms, and spermicides reduces the risk of acquiring certain infections. At present, hepatitis B is the only STD for which a safe, effective vaccine is available. Use of oral antibiotics cannot be recommended. Postcoital washing or urination have not been shown to have a protective effect against infection. Because of the potential benefits, persons at risk for STDs should be encouraged to modify their sexual behavior and use barrier methods and spermicides to protect themselves against sexually transmitted infections.